I'm using Victek's Tomato RAF (mod) and I highly recommend it:
http://victek.is-a-geek.com/tomatoen.html
I've been happily using Tomato since v1.25 (2009) but after upgrading to v1.28 I started experiencing a higher rate of errors and connection drops. As a result I had to reboot the router almost every day. That's when I found Victek's RAF mod and after installing it all the problems were gone - after using it for about an year now I never had to reboot the router due to a bad performance yet.
The advantages of the Victek's mod over the original Tomato firmware are:
- updated more frequently;
- various performance optimizations (on WRT54GL runs noticeably better than the original one);
- contains some additional features.

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